1. Field of the Invention
This invention relates to rollers for advancing paper sheets into paper folding machines, and more particularly to a universal roller for use with glue applying paper folding machines, which roller includes a plurality of detachable, spaceable segmented roller elements, carried on a metal shaft.
2. Description of the Prior Art
In certain paper folding machine operations, it is necessary and desirable to be able to apply lines of glue to the paper sheets prior to folding so that they may be folded and bound in the folding machine. Examples of products obtained by using papers with glue lines thereon would be double lottery tickets, wallets, and multiple page documents. It is important that none of the glue which is laid down on the paper sheets prior to folding, actually get on the surfaces of the rollers which transport the paper sheets, as the paper sheets would then stick to the roller and interfere with the machine's operation.
The common practice in the folding machine industry when it is desired to lay down glue lines on paper sheets, is to groove the roller or set of rollers which pick up the paper at the glue locations. With this approach, every time the location of the glue lines are changed it is necessary to remove and groove the roller or rollers or to install other rollers, all of which is awkward, expensive, and time consuming.
Various rollers have been used in folding machines for paper advancement, such as those disclosed in the U.S. patent to Shuster No. 3,796,423; and Moll No. 4,375,971, which while suitable for paper advancement, would not be useful for advancing paper sheets with glue lines without drastic modifications which could defeat their intended purpose, and/or result in the problems described above.
Moll in U.S. Pat. No. 4,650,454 describes a glue applying roller for folding machines which is satisfactory, but which includes a plurality of helical grooves separating a plurality of flat faces on the outer covering, and may not be desirable for all applications.
The universal roller of the invention provides a surface for paper engagement and a plurality of roller elements on a shaft, with easy placement and replacement of the roller elements, to accommodate different numbers and spacings of gluing lines.